Method of closing detector combs of jet weaving looms



Nov. 27, 1962 v. svAw ETAL 3,965,770-

METHOD OF CLOSING DETECTOR COMBS OF JET WEAVING LOOMS Filed Nov. 21, 1960 2 Sheets-Sheet 1 //MM;' fr INVENTORS Nov. 27, 1962 v. SVATY' ETAL 3,065,770

METHOD OF CLOSING DETECTOR COMBS OF JET WEAVING LOOMS Filed Nov. 21, 1960 2 Sheets-Sheet 2 -kw x [ma United States Patent Ofitice 3,965,770 Patented Nov. 27, 1962 3,065,770 METHOD OF CLOSING DETECTQR COMES F JET WEAVING LQOMS Vladimir Svaty and Jifi Lihansky, Brnensha, Liberec, Czechoslovakia, assignors to Sdruzeni podniku textil-= niho strojirenstvi, Liberec, Czechoslovakia Filed Nov. 21, 196i Ser. No. 70,664 Claims priority, application Czechoslovakia Nov. 21, 1%9 6 Claims. (Cl. 139-127) For jet weaving pneumatic looms a special comb composed of a row of guide members is used for directing the air stream which takes along the weft through the shed. The guide members form an air passage and have gaps allowing the weft to pass out of the comb prior to the blow of the slay. It is therefore necessary to design the individual guide members not only from the point of View of aerodynamics but also from the point of view of the mechanics of their function as weft inserting element of the textile machine i.e. each guide member has to be designed so that its entrance into the shed and the pulling out of the weft from the comb at the time the same leaves the shed takes place in the most advantageous manner. Presently used designs of such guide members are substantially characterized by a guiding opening of approximately circular shape with an outlet gap for pulling out the weft. In the known constructions, the outlet gaps of the circular guiding openings of the guide members permit the escape of air by this way and thus the weft taken along by the air stream during insertion occasionally leaves the comb through the outlet gaps.

It is an object of this invention to overcome this drawback without mechanically closing of the gaps of the comb at the moment of the Weft insertion.

It has been found that the weft can be prevented from leaving the comb by a new methodof closing the gaps of the guide members of the comb at the time of weft insertion by the choice of a suitable position of the comb at the time of Weft insertion.

In accordance with this invention the outlet gaps of the guide members of the comb are at the same time of the Weft insertion closed by one of the work systems of the shed. The angle ofan extension of a bent leg of the guide member is chosen so as to coincide at this moment with the plane defined by the closing shed threads. The comb has at the moment of shooting such a vertical position, that the said extensions of its guide members project over the plane of the closing shed threads.

Further advantage and characteristic features of this invention are obvious from the following description and drawing in which FIG. 1 is a side view, and FIG. 2 is a front view of a guide member of the comb in the weft inserting position.

As shown in the drawing, the individual guide members ll forming the comb are fixed on the slay 2, which also supports the reed 3, and are composed of straight end portions 4 and 10, and of a bent part 5 which form an inner guiding opening 6. The openings 6 form a passage through which the weft has to pass during insertion into the warp shed, taken along by the air stream. A gap 7 is formed between the ends of the straight end portions 4 and it), through which the inserted weft passes at the time the comb leaves the shed and is in the illustrated position. The shed is formed by a system of upper warp threads 8 and of lower Warp threads 9. The bent leg part 5 is terminated by the straight end portions 1th which has such an angle of inclination, that it is located in the illustrated we'ft inserting position in the plane of the shed warp threads 8, only slightly projecting from the plane of the upper shed warp threads 8, so that warp threads 8 close the gaps 7 of the guide members, since the warp 8 extends between the ends of portions 4 and 10.

In prior art constructions, the weft thread, shot through passage formed by the guiding opening 6 occasionally passed through the gaps 7 of the comb, so that it left the region of the air stream in the air guiding passage in the weft insertion could not be correctly accomplished.

When the comb is position according to this invention during weft insertion, the weft thread strikes the upper shed threads 8 and as its major part remains still within the region of the air passage formed by openings 6, it is again straightened within the guiding passage 6 and a correct insertion is accomplished since the weft cannot escape through the outlet formed by gaps 7.

The closing of the comb can be accomplished both by the upper and by the lower part of the shed threads. In the illustrated embodiment, the straight end portions of the row of aligned guide members forming the comb, are located in the plane of the upper side of the warp shed, so that warps extend between the guide members parallel to the straight end portion 10 and over the gaps 7.

We claim:

'1. The method of preventing the escape of a weft from the partly open air guiding passage of the comb of a pneumatic loom during insertion of the weft, comprising the steps of moving the comb in a warp shed to and from a terminal position in which said partly open passage is closed by the warps forming one side of the shed; and inserting the weft in said terminal position.

2. The method of preventing escape of a weft through the weft outlet openings of the air guiding passage of the comb of a jet weaving loom during insertion of the weft, comprising the steps of moving the comb in a warp shed to and from a position in which the warps forming one side of the-shed extend parallel to portions of said comb and along said outlet openings; and pneumatically inserting the weft through said passage in said position of said comb so that the weft is retained in said passage during insertion by warp portions extending over said outlet openings.

3. The method of claim 2 wherein said comb is moved to a position in which the warps forming the upper side of the shed extend parallel to said portions of said comb and over said outlet openings to retain the weft in said passage.

4. In a pneumatic loom, in combination, a comb comprising a row of aligned guiding members, each guiding member forming an inner opening and having two end portions with ends forming a narrow gap extending from said opening to the outside of the respective guiding member, said inner openings being aligned to form a passage for guiding a jet of air and a weft carried by the same, and said gaps being aligned to form an elongated outlet from said passage, said comb being movable to and from a position in which the warps of one side of a shed extend along said gaps and between the ends of said end portions; and means for placing said comb in said position during insertion of a weft into the shed through said passage whereby weft portions tending to escape through said gaps during insertion of the weft are retained by the warps extending along said gaps.

5. In a pneumatic loom, in combination, a comb com prising a row of aligned guiding members, each guiding member forming an inner opening and having two end portions with ends forming a narrow gap extending from said opening to the outside of the respective guiding member, at least one of said end portions being straight, said inner openings being aligned to form a passage for guiding a jet of air and a weft carried by the same, and said gaps being aligned to form an elongated outlet from said passage, said comb being movable to and from a position in which the warps of one side of a shed extend parallel to said straight end portion and between said straight end portions of adjacent guiding members along said gaps and between the ends of said end portions; and means for placing said comb in said position during insertion of a weft into the shed through said passage whereby weft portions tending to escape through said gaps during insertion of the weft are retained by the warps extending along said gaps.

6. In a pneumatic loom, in combination, a comb comprising a row of aligned guiding members, each guiding member forming an inner opening and having first and second straight end portions extending at an acute angle to each other and having ends forming a narrow gap extending from said opening to the outside of the respective guiding member, said inner openings being aligned to form a passage for guiding a jet of air and a weft carried by the same, and said gaps being aligned to form an elongated outlet from said passage, said comb being movable to and from a position in which the warps of upper side of a shed extend between said first straight end portions of adjacent guiding member parallel to said first straight end portions and from said first end portions of adjacent guiding members along said gaps and between said ends of said end portions; and means for placing said comb in said position during insertion of a weft into the shed through said passage whereby weft portions tending to escape through said gaps daring insertion of the weft are retained by the warps extending along said gaps.

References Cited in the file of this patent FOREIGN PATENTS 1,196,635 France May 25, 1959 638,068 Germany Nov. 9, 1936 366,473 Italy Dec. 28, 1938 

